Gaseous fuel systems commonly include a fuel tank and fuel lines leading to a stationary or mobile consumer, such as a locomotive engine. Periodically, the systems should be evacuated to maintain a desired pressure or when fuel lines are to be disconnected.
Ventilation of fuel lines to atmospheric conditions can generate long penetration sprays having a low temperature and/or a high level of noise. It is desirable to control the expansion of vented gas to reduce the penetration depth and also the temperature and sound level of the gas to within acceptable limits. This is often accomplished by placing a suppressor over an end of the vent line. However, known suppressors are designed with a focus on reducing the sound level without specific regard to a temperature of the vented fluid. Further, typical suppressors become clogged over time, resulting in increased backpressure on the fuel system and requiring periodic replacement.
An exemplary suppressor is disclosed in U.S. Pat. No. 3,718,208 (the '208 patent) that issued to Gibel on Feb. 27, 1973. The '208 patent discloses a suppression device for pneumatically operated tools and pressurized systems where a backpressure of the system must not exceed a predetermined value. The device comprises a domed head, a cylindrical body, and an end closure. An opening of the head is threaded so the device can be connected to an exhaust pipe. An expansion chamber and a silencing chamber are disposed inside the device and separated by a porous disseminator. The silencing chamber comprises a tubular wall of highly porous material that provides a tortuous flow path through which fluid passes and loses energy as it is exhausted. When the porous material becomes clogged, pressure in the device increases and forces open a valve that is normally kept closed by a spring. When the valve is forced open, noise produced by the system increases and warns the operator that the device needs to be replaced.
Although the device of the '208 patent may be somewhat effective at suppressing sound levels, its effectiveness is reduced after it becomes clogged. In particular, sound levels may not always be suppressed to a desired level because the sound increases when the device clogs and the valve is opened. Clogging can require periodic replacement, which raises a cost of operation. The device may also lack broad applicability to vent gases that undergo a significant temperature change during suppression.
The disclosed suppressor is directed to overcoming one or more of the problems set forth above and/or other problems of the prior art.